Introduction to PDA's

Introduction

A PDA (Personal Digital Assistant, also called a pocket organizer) is a pocket computer composed of a processor, RAM (Random Access Memory), a touch sensitive screen, and network functions bundled in an extremely small compact case.

PDA Use

A PDA is a pocket computer originally designed as an organizer. A personal assistant generally supplies the following standard applications:

    an agenda to organize time, with visual or mechanical reminders. Meetings or planned events can be contextualized in order to meet professional and personal requirements thanks to an adaptable classification system (office, private, etc.).
    a task manager that serves as a reminder for tasks to be done. The priority, deadlines or reminders can be assigned to each task.
    an address book (contact manager) that provides instant contact information (phone number, mailing address, email, etc.).
    email software that allows messages to be received and sent.


Personal assistants offer light versions of office automation tools such as text editors, spreadsheets, a calculator, and viewers for a wide variety of file formats (PDF files, images, etc).

In addition to these basic functions, more and more PDA’s offer advanced multimedia tools for playing videos (in different formats, including DivX format), music (notably in mp3 format) and Flash animation.

PDA’s are also used with increasing frequency for geo-referencing, mapping and road navigation by plugging them into a geo-reference device (GPS, Global Positioning System). In effect, it is possible to obtain a compatible, low cost and high performance GPS that helps with road navigation a using a map that continually displays the user’s location, speed and a visual representation of the road (eventually in 3D) with instructions both on-screen and from a synthesized voice.
Operating System

PDA’s have operating systems adapted to their screen resolution and whose features correspond to the characteristics of the device.

Many types of operating systems exist for PDA’s, usually different for each type of PDA and each manufacturer, the same as there are Mac and PC computers. The two main operating systems are:

    PalmOS, marketed by Palm.
    Windows Mobile or Pocket PC (formerly Windows CE), marketed by Microsoft.


These two systems have almost the same characteristics and the same functions, but with different methods of holding them and with incompatibilities between systems.

Note that there are Linux operating systems that were specifically developed for both types of machines.

Technical Characteristics

When purchasing a PDA, it is important to pay attention to the following characteristics:

    weight and size: PDA’s are designed to be carried everywhere and must therefore fit into hands and pockets. Its size and weight must be as small as possible, bearing in mind ergonomic requirements and screen size.
    autonomy: A PDA’s autonomy is a function of its battery’s characteristics.
        Ni-Cad (Nickel / Cadmium): a type rechargeable battery now obsolete due to its memory effect, meaning a progressive reduction of the maximum charge when it is recharged before being completely "empty".
        Ni-Mh (Nickel / Metal Hybrid): a type of rechargeable battery with higher performance than nickel-cadmium batteries.
        Li-Ion (Lithium / Ion): a type of rechargeable battery that is found in most computers. Li-Ion batteries give excellent performance for a moderate cost. As well, Li-Ion batteries do not suffer from memory effects, which means that they can be recharged before becoming completely empty.
        Li-Polymer (Lithium / Polymer): a type of rechargeable battery with performance similar to that of Li-Ion batteries, but made much lighter by replacing the electrolyte fluid and the micro-porous separator of Li-Ion batteries with a much lighter solid polymer. However, the recharging time is longer and their life expectancy is shorter.